Historically, large telephone service operations, such as customer service centers, separate inbound calling and outbound calling as separate operations. Each operation is governed by its own set of operational rules and objectives. Inbound calls are typically handled by a stand-alone automatic call distributor (ACD). The goal of the inbound call servicing operation is to provide optimum response, which is usually defined as the speed of response to an arriving call by an operator or agent. This is measured by the average speed Of answer (ASA). Other service quality definitions, such as abandonment rate, may be used. The abandonment rate indicates the number of customers who hang up while on hold.
The arrival rate of inbound call traffic is generally assumed to be a random process with a Poisson distribution based on the average arrival rate. The Poisson arrival process assumes that the arrival time of any one particular call is independent of the arrival time of any other call. From these statistics, a manual forecast of agent requirements is made based on the Erlang-C model. This is normally used in an inbound calling environment to schedule agents. Matching these agents' schedules to the random arrival rate of inbound calls is a source of inefficiency in the inbound call operation. If a large number of agents relative to the expected traffic is scheduled, the utilization of these agents will be low, although the quality of service to the caller will be high. If a small number of operators relative to the expected traffic is scheduled, the ASA will be poor, although the agent utilization will be high.
The arrival rate of inbound call traffic is further complicated by variations in traffic rate which are not addressed by the Erlang-C model. Such variations can be due to unexplained causes and consequently cannot be forecasted. This leads to large mismatches between actual traffic levels and staffing levels in spite of diligent efforts to match staffing with expected traffic levels. The mismatches between inbound call traffic and staffing cannot be completely eliminated by staff planning efforts. The result is rampant chronic overstaffing, resulting in poor agent utilization, or understaffing, resulting in poor customer service in inbound calling operations.
Outbound calls are typically handled by a stand-alone outbound dialer. Its goal is to maximize agent utilization by maximizing the number of valid telephone connections for a given population of agents and distribution of call characteristics. The connection rate of outbound traffic is controlled by the outbound dialer. Unlike the inbound call servicing operation, the outbound call servicing operation is not random. The connection rate can be adjusted to accommodate the pool of available agents. Because the inbound and outbound call servicing operations have different operational rules and objectives, they are treated as separate operations despite the inefficiency in agent utilization.
Therefore, it can be appreciated that a need exists to combine the pool of agents available to service inbound calls with the pool of agents available to service outbound calls so as to optimize agent efficiency while maintaining service quality in both inbound and outbound call servicing operations.